1. Field of the Invention
The present invention relates to electronic camera apparatus with a moving-image pickup function and moving-image recording methods.
2. Description of the Related Art
In the past, typical digital cameras with a moving-image pickup function have recording media removably set on bodies thereof. In such digital camera, main three methods of recording a moving image on a recording medium are used. One of these methods comprises temporarily and sequentially storing data on moving frame images picked up at predetermined frame rates on an internal memory to/from which the image data can be read/written at high speeds and when the image pickup is terminated, storing all such data collectively on a separate recording medium. Another method comprises writing flame data in a buffer area for a plurality of frame images secured in the internal memory, simultaneously reading out the previous stored frame data, storing it on the recording medium, erasing the frame data from the internal memory, and then repeating these operations. In this case, the internal memory is used as a ring buffer. The last method comprises sequentially recording frame data on a recording medium, which method is generally referred to as streaming.
These three methods have merits and demerits. In terms of successively image-pickable-up or -recordable time, the last-mentioned method is most advantageous. In terms of data write speed performance required from recording media, or a data quantity writable per unit time to be required, the first-mentioned method is most advantageous.
Published unexamined Japanese Patent Application 2001-352510 discloses a digital camera in which still and moving image data having smaller and larger data quantities per unit time are recorded on two different removable recording mediums having known lower and higher write speeds, respectively, in order to prevent moving-image frame data and/or associated sounds from becoming missing and/or disappearing during recording.
Even when the method of recording the moving-image data is fixed in the digital camera with the moving-image pickup function as described above, the user can select a recording quality of the moving picture (for example, fine, normal or economical), thereby automatically setting recording parameters (indicating a data compression rate, an image size and a frame rate) determined for that recording quality in the image pickup.
However, the write speed performance of recording media that will be used in the digital camera varies depending on the type (or standard) of the media. In addition, even when recording media have the same standard, they actually vary from maker to maker. Thus, the upper limit of the recording quality settable in the moving-picture pickup need be set to the general write speed performance of settable recording media of a type to be used, or to a lower recording quality in which the moving image data is recordable sufficiently. Thus, when a recording medium having higher write speed performance than the general one beforehand presumed is used, its write speed performance cannot be sufficiently brought into full play.